Composition Of Leukocyte Subsets Research Articles

ПОПУЛЯЦІЙНИЙ СКЛАД ЛЕЙКОЦИТІВ ПЕРИФЕРИЧНОЇ КРОВІ У ЩУРІВЗ РІЗНИМИ МОДЕЛЯМИ ХВОРОБИ АЛЬЦГЕЙМЕРА

Background. Systemic inflammation is recognized a sone of the key features of Alzheimer's disease (AD) – a neurodegenerative disorder, which is characterized by cognitive decline with progressive memory loss and affects millions of predominantlyeld erly people. Recent literature data suggest the involvement of periphera limmune cells in the initiation and progression of AD. However, our understanding of the population composition of peripheral blood leukocytes and its contribution to disease progression remains limited. The use of anima lmodels plays an important role in investigating possible mechanisms linking the periphera limmune system to the inflammatory processes underlying neurode generation. The aim of this study was comparative assessment of the composition of leukocyte subsets in rats with AD, induced by intrahippocampa linjection of amyloidbeta (Aβ) 1–40 and Aβ 25–35. Methods. Male Wistar rats were used in the experiments, including intact and sham-operated animals as controls. Disease development was confirmed b y assessing cognitive impairment in the Barnesmaze be havioral test and by the loss of dopaminergic neurons. Hematological parameters were evaluatedat the end of the experiment (day 37 after the disease initiation), including absolute leukocyte count, as well as absolute and relative count of their main subsets: lymphocytes, monocytes, andneutrophils. Rats with AD induced by Aβ 1–40 exhibited granulocytosis (a fivefold increase in absolute granulocyte countin the circulation). Absolute and relative count of lymphocytes In these animals were decreased on average by 2.5 times, monocyte count – on average by 3 times as compared to those in intactand sham-operated rats.In rats with Αβ 25–35-induced AD, leukocytosis with slightly decreased lymphocyte proportion, increase in monocyte count twice at average and unchanged neutrophil countwere revealed. Results. Therefore, animalswith AD, inducedby Aβ 1–40, had hematologic markers of systemic inflammation (leukocytosis, granulocytosis, lymphocytopenia, andmonocytopenia). Conclusions. These results suggest that the Aβ 1–40-induced AD model more accurately reproduces the hematologic signs of systemic inflammation observed in patients with this pathology.

Skewed fate and hematopoiesis of CD34+ HSPCs in umbilical cord blood amid the COVID-19 pandemic.

Umbilical cord blood (UCB) is an irreplaceable source for hematopoietic stem progenitor cells (HSPCs). However, the effects of SARS-CoV-2 infection and COVID-19 vaccination on UCB phenotype, specifically the HSPCs therein, are currently unknown. We thus evaluated any effects of SARS-CoV-2 infection and/or COVID-19 vaccination from the mother on the fate and functionalities of HSPCs in the UCB. The numbers and frequencies of HSPCs in the UCB decreased significantly in donors with previous SARS-CoV-2 infection and more so with COVID-19 vaccination via the induction of apoptosis, likely mediated by IFN-γ-dependent pathways. Two independent hematopoiesis assays, a colony forming unit assay and a mouse humanization assay, revealed skewed hematopoiesis of HSPCs obtained from donors delivered from mothers with SARS-CoV-2 infection history. These results indicate that SARS-CoV-2 infection and COVID-19 vaccination impair the functionalities and survivability of HSPCs in the UCB, which would make unprecedented concerns on the future of HSPC-based therapies.

Alterations of macrophage and neutrophil content in skeletal muscle of aged versus young mice.

BackgroundSkeletal muscle inflammation and oxidative stress are associated with aging‐related loss of muscle mass and may be attributable to alterations in the number and types of leukocytes in skeletal muscle. Here, we tested the hypothesis that aging changes the number and composition of leukocyte subsets in skeletal muscle tissue.MethodsSkeletal muscle was sampled from 4‐mo‐old (young) and 27‐mo‐old (old) C57BL/6J mice. Mononuclear cells of the gastrocnemius muscle were isolated, and flow cytometry was used to characterize the number and types of immune cells.ResultsThe number of neutrophils and Ly‐6C+ inflammatory macrophages in the skeletal muscle was significantly higher in old mice than in young mice. Inflammation and oxidative stress (measured using the markers phosphorylated JNK and nitrotyrosine) were also higher in the skeletal muscle of old mice than in that of young mice.ConclusionsIncreasing age promotes skeletal muscle inflammation and oxidative stress, as well as infiltration of inflammatory macrophages and neutrophils.

Long telomere length in circulating leukocytes is associated with monocytosis and poorer survival in patients with transcatheter aortic valve replacement

Abstract Background Whiletranscatheter aortic valve replacement (TAVR) has become a standard treatment option in the management of patients with severe aortic stenosis and higher risk for cardiac surgery, occurrence of a systemic inflammatory response after TAVR limits patients' prognosis. Leukocyte telomere length (LTL) is an established marker of cellular senescence and longer telomeres are hallmarks of immune competence and inflammatory responsiveness of leukocyte subsets. In the present study, we assessed LTL and its impact on 2-year survival in patients (pts) following TAVR. Methods and results LTL was analyzed using quantitative real-time PCR in 285 consecutive pts (mean age 80.9 years, 49% male) undergoing TAVR and correlated with 2-year all-cause mortality (46 deaths, 16%). Kaplan-Meier survival curves showed that the highest compared to lowest tertile of LTL was associated with an increased rate of all-cause mortality (log rank p=0.03). Multivariate regression model revealed higher EuroSCORE 2 (HR: 1.03, 95% CI: 1.01–1.05; p=0.021) and long LTL (HR: 1.001, 95% CI: 1.001–1.001; p=0.023) to be independent predictors for 2-year mortality, after adjustment for clinical variables such as age, sex, cardiovascular risk factors, LVEF and renal function. When analyzing blood leukocyte subset composition, pts in the highest LTL tertile showed significantly higher levels of circulating neutrophils (p=0.011) and monocytes (p=0.011), whereas there was no significant correlation between LTL and lymphocyte counts (p=0.12). Conclusion In elderly patients with severe aortic valve stenosis, long leukocyte telomere length is associated with increased mortality after TAVR. This might be explained by enhanced immune competence and increased pro-inflammatory leukocyte function in these patients as indicated by significant monocytosis, which might drive systemic inflammatory response syndrome or chronic inflammation and limit the prognosis in TAVR patients. Funding Acknowledgement Type of funding source: None

Rat peripheral blood leukocyte subset composition, hemogram, lymphoid organ and body morphometry after exposure to biologically active substances derived from Hirudo verbana saliva

Medical community has noted that the prevalence of allergic diseases by steadily tends to rise resulting from using synthetic drugs ecological catastrophe. In this regard, more and more attention is increasingly being paid to natural therapeutic approaches, one of which is based on applying hirudotherapy. There were used 40 pubescent outbred female rats and their 200 pups born during experiment. In particular, female rats underwent leeching in the subscapular region 2 weeks before and 2 weeks after mating by applying medical leeches weighing 400 ± 10 mg. Next, relevant progeny was examined at day 1, 15, 30, 45, and 60 after birth, whereas female rats– after weaning. Experiment was designed to assess diverse parameters in accordance with the age-related rat development: newborn pups – 1-5 days old, day 6-21 – suckling period, day 22-50 – onset of puberty, day 60 onward – puberty. After measuring body morphometric parameters, female rats were sacrificed by decapitation under ether narcosis on day 60, whereas rat pups – at various time points. followed by autopsy and collecting blood sample into a sterile centrifuge tube by using 2% Spofa crystalline heparin (8:1) to be further examined by standard assays: morphometry of rat body, spleen and thymus; measuring total leukocyte count; CBC with differential; RBC; hemoglobin level; color index. Statistical data processing was performed by calculating arithmetic mean, error of arithmetic mean, standard deviation by using SPSS version 21.0 and Microsoft Office Excel 2010 software. Significance of differences was estimated by using Student's t test, and set at p≤0.05. Our study demonstrated medical leech saliva components applied during hirudolotherapy exerted an immune-augmenting effect of on morphometric body, thymus and spleen parameters. Moreover, starting from day 1, total leukocyte count, RBC, and hemoglobin level were increased in the experimental group. Moreover, we convincingly demonstrated a stimulatory effect of medical leech saliva components on histogenetic reactions at various ontogenetic stages in both female rats and their progeny. In the former, such morphogenetic effect was maintained for more than 70 days after the last leeching: on week 2 after mating and 30 days after delivery. Changes in morphological and hematological evidence about enhanced morphogenetic function of immune system in response to saliva-derived biologically active substances released by medicinal leeches.

A Disease-Associated MicroRNA Cluster Links Inflammatory Pathways and an Altered Composition of Leukocyte Subsets to Noninfectious Uveitis.

The cause of noninfectious uveitis (NIU) is poorly understood but is considered to be mediated by a complex interplay between genetic, environmental, and-relatively unexplored-epigenetic factors. MicroRNAs (miRNAs) are noncoding small RNAs that are important epigenetic regulators implicated in pathologic signaling. Therefore, we mapped the circulating miRNA-ome of NIU patients and studied miRNA perturbations within the broader context of the immune system. We designed a strategy to robustly identify changes in the miRNA profiles of two independent cohorts totaling 54 untreated patients with active and eye-restricted disease and 26 age-matched controls. High-resolution miRNA-ome data were obtained by TaqMan OpenArray technology and subsequent RT-qPCR. Flow cytometry data, and proteomic data spanning the cellular immune system, were used to map the uveitis-miRNA signature to changes in the composition of specific leukocyte subsets in blood. Using stringent selection criteria, we identified and independently validated an miRNA cluster that is associated with NIU. Pathway enrichment analysis for genes targeted by this cluster revealed significant enrichment for the PI3K/Akt, MAPK, FOXO, and VEGF signaling pathways, and photoreceptor development. In addition, unsupervised multidomain analyses linked the presence of the uveitis-associated miRNA cluster to a different composition of leukocyte subsets, more specifically, CD16+CD11c+HLA-DR- cells. Together, this study identified a unique miRNA cluster associated with NIU that was related to changes in leukocyte subsets demonstrating systemic changes in epigenetic regulation underlying NIU.

Comparison of Human Neonatal and Adult Blood Leukocyte Subset Composition Phenotypes

The human peripheral leukocyte subset composition depends on genotype variation and pre-natal and post-natal environmental influence diversity. We quantified this composition in adults and neonates, and compared the median values and dispersal ranges of various subsets in them. We confirmed higher frequencies of monocytes and regulatory T cells (Tregs), similar frequencies of neutrophils, and lower frequencies of CD8 T cells, NKT cells, B1 B cells and gamma-delta T cells in neonatal umbilical cord blood. Unlike previous reports, we found higher frequencies of eosinophils and B cells, higher CD4:CD8 ratios, lower frequencies of T cells and iNKT cells, and similar frequencies of CD4 T cells and NK cells in neonates. We characterized monocyte subsets and dendritic cell (DC) subsets in far greater detail than previously reported, using recently described surface markers and gating strategies and observed that neonates had lower frequencies of patrolling monocytes and lower myeloid dendritic cell (mDC):plasmacytoid DC (pDC) ratios. Our data contribute to South Asian reference values for these parameters. We found that dispersal ranges differ between different leukocyte subsets, suggesting differential determination of variation. Further, some subsets were more dispersed in adults than in neonates suggesting influences of postnatal sources of variation, while some show the opposite pattern suggesting influences of developmental process variation. Together, these data and analyses provide interesting biological possibilities for future exploration.

Neonatal microbial colonization in mice promotes prolonged dominance of CD11b(+)Gr-1(+) cells and accelerated establishment of the CD4(+) T cell population in the spleen.

To assess the microbial influence on postnatal hematopoiesis, we examined the role of early life microbial colonization on the composition of leukocyte subsets in the neonatal spleen. A high number of CD11b+Gr-1+ splenocytes present perinatally was sustained for a longer period in conventionally colonized (CONV) mice than in mono-colonized (MC) and germfree (GF) mice, and the CD4+ T cell population established faster in CONV mice. At the day of birth, compared to GF mice, the expression of Cxcl2 was up-regulated and Arg1 down-regulated in livers of CONV mice. This coincided with lower abundance of polylobed cells in the liver of CONV mice. An earlier peak in the expression of the genes Tjp1, Cdh1, and JamA in intestinal epithelial cells of CONV mice indicated an accelerated closure of the epithelial barrier. In conclusion, we have identified an important microbiota-dependent neonatal hematopoietic event, which we suggest impacts the subsequent development of the T cell population in the murine spleen.

Minimal changes in the systemic immune response after nephrectomy of localized renal masses

ObjectivesRenal cell carcinoma (RCC) is an immunogenic tumor, and multiple immunostimulatory therapies are in use or under development for patients with inoperable tumors. However, a major drawback to the use of immunotherapy for RCC is that renal tumors are also immunosuppressive. As a result, current immunotherapies are curative in<10% of patients with RCC. To better understand the systemic immune response to RCC, we performed a comprehensive examination of the leukocyte and cytokine/chemokine composition in the peripheral blood of patients with localized clear cell renal tumors pre- and post-nephrectomy. Methods and materialsPeripheral blood samples were taken from 53 consented subjects with renal masses before cytoreductive nephrectomy and again at clinic visits approximately 30 days after nephrectomy. Samples were also obtained from 10 healthy age- and gender-matched controls. Blood samples from clear cell RCC subjects were analyzed by multi-parameter flow cytometry to determine leukocyte subset composition and multiplex array to evaluate plasma proteins. ResultsPre-nephrectomy, clear cell tumors were associated with systemic accumulations of both “exhausted” CD8+ T cells, as indicated by surface BTLA expression, and monocytic CD14+HLA-DRnegCD33+ myeloid-derived suppressor cells (MDSC). Subjects with T3 clear cell RCC also had a unique pro-tumorigenic and inflammatory cytokine/chemokine profile characterized by high serum concentrations of IL-1β, IL-2, IL-5, IL-7, IL-8, IL-17, TNF-α, MCP-1 and MIP-1β. At an early post-nephrectomy time point (~30 d), we found the systemic immune response to be largely unaltered. The only significant change was a decrease in the mean percentage of circulating BTLA+CD8+ T cells. All other cellular and soluble immune parameters we examined were unaltered by the removal of the primary tumor. ConclusionsIn the first month following surgery, nephrectomy may relieve systemic CD8 T cell exhaustion marked by BTLA expression, but continuing inflammation and MDSC presence likely counteract this positive effect. Future determination of how this systemic immune signature becomes altered during metastatic progression could provide novel targets for neoadjuvant immunotherapy in RCC.

AB0079 Anti-c5a receptor antibody treatment ameliorates disease activity in delayed-type hypersensitivity (dth) arthritic mice

BackgroundC5a is an anaphylatoxin generated in response to complement activation. C5a promotes leukocyte chemotaxis and activation via the C5a receptor (C5aR), both directly on C5aR-positive cells such as neutrophils, monocytes...

Phenotypic alteration of blood and milk leukocytes in goats naturally infected with caprine arthritis-encephalitis virus (CAEV)

Caprine arthritis-encephalitis virus (CAEV) causes a persistent and slow progressive infection in goats, characterized by chronic proliferative sinovitis, arthritis and, less frequently, pneumonia. Infected goats can also be affected by interstitial mastitis. The aim of this study was to evaluate the influence of CAEV infection on the phenotypic composition of leukocyte subsets in blood and milk, during lactation. CD8 positive cells in blood and milk were more numerous in CAEV positive goats when compared to negative goats. γδTcR positive cells were higher in blood but not in milk of CAEV positive goats. The content of cells expressing MHC class II molecules was higher in blood from CAEV negative goats, while the content of activated cells was higher in milk from CAEV infected goats.

Postnatal Life Events Affect the Severity of Asthmatic Airway Inflammation in the Adult Rat

Genetic and hygienic factors influence susceptibility to asthma. In autoimmune and inflammatory diseases, additional effects of the psychosocial environment have been demonstrated that might also play a role in asthma. In this study, the impact of different early postnatal stressors on an OVA-induced model of asthma was tested in adulthood. Fischer 344 rats were subjected to either repeated handling stimulation (HA), maternal separation (MS), or were left undisturbed in their first 4 wk of life. Behavioral differences were characterized at the age of 4 mo. At 5 mo of age, immunological cellular and serologic changes were investigated and experimental asthma was induced. Results show significantly increased exploratory behavior and reduced anxiety in HA rats compared with MS and controls. Without further behavioral or immunological challenges, HA animals exhibited an increased ex vivo NK cell cytotoxicity but no other obvious immunological differences. After induction of asthma, in contrast, MS animals exhibited proinflammatory effects in leukocyte subset composition including increased eosinophil numbers, whereas levels of IgE and the allergy-specific cytokine IL-13 were reduced compared with HA. There was a most remarkable increase of adrenocorticotropin in HA animals, comparing pre- to postchallenge plasma levels. These data demonstrate for the first time that early postnatal stimulative or adverse experiences exert long-lasting changes of the "neuroendocrinoimmune" interface in adulthood, resulting in either protective or aggravating mechanisms in allergic airway disease. Thus, in addition to genetic and hygienic factors, nongenetically acquired individual differences contribute to the pathobiology of asthma.

IL-21 induces in vivo immune activation of NK cells and CD8+ T cells in patients with metastatic melanoma and renal cell carcinoma

PurposeHuman interleukin-21 (IL-21) is a class I cytokine previously reported in clinical studies on immune responsive cancers. Here we report the effects of systemic IL-21 therapy on the immune system in two phase 1 trials with this novel cytokine.Experimental designRecombinant IL-21 was administered by intravenous bolus injection at dose levels from 1 to 100 μg/kg using two planned treatment regimens: thrice weekly for 6 weeks (3/week); or once daily for five consecutive days followed by nine dose-free days (5 + 9). The following biomarkers were studied in peripheral blood mononuclear cells (PBMC) during treatment: phosphorylation of STAT3, alterations in the composition of leukocyte subsets, ex vivo cytotoxicity, expression of effector molecules in enriched CD8+ T cells and CD56+ NK cells by quantitative RT-PCR, and gene array profiling of CD8+ T cells.ResultsEffects of IL-21 were observed at all dose levels. In the 5 + 9 regimen IL-21 induced a dose dependent decrease in circulating NK cells and T cells followed by a return to baseline in resting periods. In both CD8+ T cells and CD56+ NK cells we found up-regulation of perforin and granzyme B mRNA. In addition, full transcriptome analysis of CD8+ T cells displayed changes in several transcripts associated with increased cell cycle progression, cellular motility, and immune activation. Finally, cytotoxicity assays showed that IL-21 enhanced the ability of NK cells to kill sensitive targets ex vivo.ConclusionsIL-21 was biologically active at all dose levels administered with evidence of in vivo NK cell and CD8+ T cell activation.Electronic supplementary materialThe online version of this article (doi:10.1007/s00262-008-0479-4) contains supplementary material, which is available to authorized users.

Postnatal development of leukocyte subset composition and activity in dogs

The aim of the presentation is to summarise our data on the counts and activity of circulating canine leukocytes at birth and on their changes in the first 3 months of life. On day 1, neutrophil counts were almost three times higher than lymphocyte counts. During the first week of life, a decrease of neutrophil and an increase of lymphocyte counts, resulting in a predominance of lymphocytes, were observed. Neutrophil counts reached values comparable with those in adults in 1 month. Lymphocyte counts were higher than those in adults during the first 3 months. From birth to the age of 3 months, the phagocytic activity of neutrophils was nonsignificantly higher than in young adults. When compared with adults, the peripheral blood of new-born pups contained a lower proportion of T lymphocytes (detected by CD3 and CD5 markers), with a very low percentage of CD8 + cells and a higher proportion of CD21 + B lymphocytes. The counts of individual subsets levelled out during the first 3 months of life, although the proportion of CD21 + B cells remained higher all the time. Lymphocytes of new-born pups were able to respond to nonspecific mitogen stimulation. Spontaneous proliferation in vitro was higher during the first week of life. Although in vitro stimulation of lymphocytes with Concanavalin A in some pups was comparable with that of adult dogs, mean activity was weaker. Pups with zero or very low levels of maternal antibodies were able to develop specific immune responses to a parvovirus antigen as early as at 2 weeks of age. On the basis of these data, we assume that pups are born with an immune system that can respond to external stimuli. Nevertheless its development continues in the postnatal period and some parameters differ from adult values for at least 3 months after birth.

Acute primary infection with cytomegalovirus (CMV) in kidney transplant recipients results in the appearance of a phenotypically aberrant CD8+ T cell population.

Human cytomegalovirus (CMV) is a beta-herpesvirus that causes a chronic subclinical infection in healthy man. The immune system is unable to eliminate the virus completely, allowing virus to persist in a latent state. In the immunocompromised host, this equilibrium is disturbed, resulting in a clinical infection. In immunocompromised rats, clinical CMV infection is associated with an increase in NK cells and CD8+ T cells, including a phenotypically aberrant CD8+ T cell population. Using flow cytometry, we examined the effect of acute CMV infection on the composition of leukocyte subsets in immunocompromised patients. Therefore, we used peripheral blood of CMV seronegative patients receiving a kidney from a seronegative (control group) or a seropositive donor. Of the patients receiving a seropositive kidney, only the patients undergoing acute CMV infection were included (experimental group). Special attention was paid to the phenotype of the cytotoxic T cells. The development of acute CMV infection resulted in an increased NK cell number and an activation of both CD4+ and CD8+ T cells, as determined by HLA-DR expression. An aberrant CD8+ T cell subset with decreased expression of CD8 and TCR alphabeta appeared in the infected patients. Furthermore, the size of this subpopulation of CD8+ T cells is positively correlated with the viral load.

Variable Leukocyte Composition of Red Blood Cell Concentrates Prepared in Top-Bottom Systems: Possible Implications for Pre-Transplant Blood Transfusion

Background and Objectives: The beneficial effect of blood transfusion on kidney graft survival requires the presence of leukocytes in the transfusate, but a minimal dose has not been defined, nor has the role of individual leukocyte subsets been investigated. In the Netherlands, a standard pre-transplant blood transfusion consists of a buffy coat (BC)-depleted red blood cell concentrate (RBCC) containing a maximum of 1.2×10⁹ residual leukocytes per unit. However, leukocyte subset composition is not standardized. Materials and Methods: Using FACS analysis, this study compared the residual leukocyte composition of RBCCs produced by Compomat^® and Optipress^®, two currently used top-bottom systems. Results: While the total leukocyte content of the RBCCs was equivalent in both press types (0.5×10⁹), the percentage of mononuclear cells (lymphocytes and monocytes) was significantly higher in the Compomat as compared with the Optipress system (p < 0.0001), resulting in significantly higher numbers of transfused T cells, B cells, HLA-DR-positive cells, NK cells and stem cells. Conclusions: The leukocyte composition of a pre-transplant blood transfusion depends on the BC depletion method used; this might differentially affect the tolerizing or immunizing potential of a pre-transplant blood transfusion.

Flow cytometric analysis of an immunodeficiency disorder affecting juvenile llamas

The present study was undertaken to characterize the immune system of llamas and alpacas and establish the basis for an immunodeficiency disorder affecting juvenile llamas. Flow cytometric (FC) analysis of the immune system with a panel of monoclonal antibodies (mAbs) revealed the immune system of llamas and alpacas is similar in leukocyte subset composition to that in ruminants. Peripheral blood mononuclear cells in adults are comprised of surface immunoglobulin (sIg +) B-cells (31%±8 S.D.), αβ T-cells (27%±12 S.D.), WC1 + γδ T-cells (16%±11 S.D.), and 5–16% monocytes. In contrast to cattle, goats, and sheep, however, the frequency of WC1 + γδ T-cells is not high in juveniles but similar to the frequency in adults. Also, sIg + B-cells are present in high concentration in juveniles (43%±11 S.D.). Expression of major histocompatibility class II molecules on resting T-cells was low or absent. Comparative analysis of peripheral blood lymphocyte composition in normal juvenile llamas and llamas presenting with the signs of the juvenile llama immunodeficiency syndrome (JLIDS) revealed the concentration of B-cells is extremely low (1–5%) in affected animals. The findings suggest JLIDS is attributable to an autosomal recessive genetic defect in the development of B-cells.

The effect of acute infection with rat cytomegalovirus on the composition of leukocyte subsets

The effect of acute infection with rat cytomegalovirus on the composition of leukocyte subsets

The effect of acute infection with rat cytomegalovirus on the composition of leukocyte subsets

The effect of acute infection with rat cytomegalovirus on the composition of leukocyte subsets